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0000720309 afiii:C000125498Member 2016-01-01 2025-12-31 0000720309 afiii:MSCIACAsiaPacificExJapanIndexMember 2016-01-01 2025-12-31 iso4217:USD pure 0000720309 false 485BPOS 2025-12-31 0.0149 0.0726 0.0515 0.0677 -0.0182 0.1110 0.0734 -0.0129 -0.1317 0.0669 -0.2791 -0.0482 0.0723 0.4157 0.1311 0.2025 -0.0376 0.2569 0.3874 0.0316 N-1A AMG FUNDS III 2026-05-01 AMG GW&K ESG Bond Fund Investment Objective <div style="line-height:10.6pt;margin-top:0.0pt;text-align:left;">AMG GW&K ESG Bond Fund’s (the “Fund”) investment objective is to generate income and capital appreciation.</div> Fees and Expenses of the Fund <div style="line-height:10.6pt;margin-top:0.0pt;text-align:left;">The table below describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</div> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0023 0.0023 0 0 0.0049 0.0029 0.0072 0.0052 -0.0004 -0.0004 0.0068 0.0048 May 1, 2027 Expense Example <div style="line-height:10.6pt;margin-top:-0.01pt;text-align:left;">This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund’s operating expenses remain the same. The first year of each amount shown in the Example reflects the Fund’s contractual expense limitation through May 1, </div><div style="line-height:10.6pt;text-align:left;">2027. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:</div> 69 226 397 891 49 163 287 649 Portfolio Turnover <div style="line-height:10.6pt;margin-top:0.0pt;text-align:left;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 35% of the average value of its portfolio.</div> 0.35 Principal Investment Strategies <div style="line-height:10.6pt;margin-top:0.00pt;text-align:left;">The Fund seeks to achieve its objective by investing in a diversified portfolio of fixed income securities. </div><div style="margin-top:6pt;">Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in bonds (debt securities). The term “bond” includes any debt or fixed income securities. Up to 30% of the Fund’s assets may be invested in below investment grade securities (commonly known as “junk bonds” or “high yield securities”). Below investment grade securities are rated below Baa3 by Moody’s Investors Service, Inc. (“Moody’s”) or below BBB- by S&P Global Ratings (“S&P”) or similarly rated by another nationally recognized statistical rating organization (“NRSRO”), or unrated but determined by GW&K Investment Management, LLC, the subadviser to the Fund (“GW&K” or the “Subadviser”), to be of comparable credit quality. In cases where the credit ratings agencies have assigned different credit ratings to the same security, the Fund will use the median rating when three NRSROs provide ratings (split-to-middle). When ratings are available from only two NRSROs, the Fund will assign the lower of the two ratings (split-to-low). The Fund may continue to hold securities that are downgraded in credit rating subsequent to their purchase if GW&K believes it would be advantageous to do so. While the Fund may purchase debt securities of any duration, the Fund currently intends to primarily invest in debt securities so that the average effective duration of the Fund’s portfolio will remain +/- 20% of the average effective duration of its benchmark, the Bloomberg U.S. Aggregate Bond Index, which was 5.88 years as of February 28, 2026. The average effective duration of debt securities in the Fund’s portfolio may, however, be shorter or longer depending on market conditions. </div><div style="margin-top:6pt;">The Fund may invest in debt securities issued by any of the following: public and private U.S. and non-U.S. companies; the U.S. government and its agencies, such as the Federal Home Loan Bank; state and local governments issuing taxable municipal securities; and governments, government agencies, </div><div style="line-height:10.6pt;text-align:left;">authorities or instrumentalities and supra-national organizations in foreign countries, including emerging markets. The Fund may also invest in asset-backed and mortgage-backed debt securities. The Fund may invest in exchange-traded funds (“ETFs”) to gain exposure to certain bond sectors such as bank loans. The Fund may also invest in Treasury Inflation Protected Securities (“TIPS”) and preferred securities. Up to 10% of the Fund’s assets may be invested in non-U.S. dollar-denominated instruments, including sovereign and corporate bonds. The Fund may also invest in bonds whose proceeds are reserved for financing the implementation of the United Nations’ Sustainable Development Goals or other sustainable projects. GW&K’s investment process involves fundamental credit research and GW&K’s analysis of how the Fund’s potential investments are affected by material environmental, social and governance (“ESG”) factors. In selecting potential investments for the Fund, GW&K uses top-down research that focuses on managing duration, yield curve, credit quality, volatility and liquidity, as well as bottom-up research that focuses on fundamental analysis, valuation analysis, technical analysis, and ESG factor analysis. GW&K may adjust its assessment of an investment based on a number of considerations. </div><div style="margin-top:6pt;">GW&K applies its ESG factor analysis as one element of the investment process when selecting debt securities issued by public and private companies, including corporate bonds and preferred securities, state and local governments issuing taxable municipal securities, and bonds whose proceeds are reserved for financing the implementation of the United Nations’ Sustainable Development Goals or other sustainable projects, but not when selecting debt securities issued by other types of issuers, including but not limited to asset-backed and mortgage-backed debt securities, ETFs, TIPS, non-U.S. dollar-dominated instruments, and securities issued by the U.S. government and its agencies, such as the Federal Home Loan Bank, and governments, government agencies, authorities or instrumentalities and supra-national organizations in foreign countries. GW&K has created its own proprietary ESG Scoring System, which takes into consideration a range of factors, including independent analysis from third parties such as MSCI Inc. and Sustainalytics, as well as its own analysis of material ESG factors. Each of GW&K’s sector specialists generally assesses the materiality of relevant environmental, social and governance metrics to bond issues during the fundamental research process, depending on the sector and for corporate issuers the nature of the company’s business. GW&K uses standards developed by the Sustainable Accounting Standards Board to inform these assessments. Environmental assessment may take into account issues such as carbon emissions, natural resource usage, hazardous waste, chemical safety, water stress and sustainable technology. Social assessment may take into account issues such as human rights, labor relations, employee safety, product safety, data security and community relations. Governance assessment may take into account issues such as business ethics, board quality, board composition, compensation practices, financial reporting and stakeholder governance. </div><div style="margin-top:6pt;">GW&K recognizes that the relative impact of ESG factors on investment performance may vary across market sector, industries and regions, but the firm believes that responsible corporate behavior with respect to ESG factors can contribute to positive and sustainable long-term financial performance. GW&K seeks to identify issuers that GW&K believes are leaders in their industries in effectively addressing exposure to ESG risks through business practices, policies and programs, or issuers </div><div style="line-height:10.6pt;text-align:left;">within an industry that have more limited exposure to ESG risks. The goal of the ESG factor analysis is to seek investments with lesser exposure to, or better management of, ESG risks.</div> There is the risk that you may lose money on your investment. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. <div style="margin-top:6pt;">Debt Securities Risk—the value of a debt security changes in response to various factors, including, for example, market-related factors, such as changes in interest rates or changes in the actual or perceived ability of an issuer to meet its obligations. Investments in debt securities are subject to, among other risks, credit risk, interest rate risk, extension risk, prepayment risk and liquidity risk.</div> <div style="margin-top:6pt;">Market Risk—market prices of investments held by the Fund may fall rapidly or unpredictably due to a variety of factors, including economic or market conditions, or other factors including terrorism, war, natural disasters and the spread of infectious illness or other public health issues, including epidemics or pandemics, or in response to events that affect particular industries or companies. In addition, unexpected political, regulatory, trade and diplomatic events within the United States and abroad may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.</div> <div style="margin-top:6pt;">Interest Rate Risk—fixed coupon payments (cash flows) of bonds and debt securities may become less competitive with the market in periods of rising interest rates and cause bond prices to decline. During periods of increasing interest rates, the Fund may experience high levels of volatility and shareholder redemptions, and may have to sell securities at times when it would otherwise not do so, and at unfavorable prices, which could reduce the returns of the Fund.</div> <div style="margin-top:6pt;">Credit Risk—the issuer of bonds or other debt securities may be unable or unwilling, or may be perceived as unable or unwilling, to make timely interest or principal payments or otherwise honor its obligations. Changes in an issuer’s financial strength, credit rating or the market’s perception of an issuer’s creditworthiness may also affect the value of the Fund’s investment in that issuer.</div> <div style="margin-top:6pt;">High Yield Risk—below investment grade debt securities and unrated securities of similar credit quality (commonly known as “junk bonds” or “high yield securities”) may be subject to greater levels of interest rate, credit, liquidity, and market risk than higher-rated securities. These securities are considered </div><div style="line-height:10.6pt;text-align:left;">predominately speculative with respect to the issuer’s continuing ability to make principal and interest payments.</div> <div style="margin-top:6pt;">ESG Investing Risk—because applying the Fund’s ESG investment criteria may result in the selection or exclusion of securities of certain issuers for reasons other than financial performance, the Fund’s investment returns may underperform funds that do not incorporate ESG factors into their investment process. The incorporation of ESG criteria into the investment process may affect the Fund’s investment exposure to certain companies, sectors, regions, countries or types of investments, which could negatively impact the Fund’s performance depending on whether such investments are in or out of favor. Applying ESG criteria to investment decisions is qualitative and subjective by nature, and there is no guarantee that the criteria utilized by the Subadviser or any judgment exercised by the Subadviser will improve the financial performance of the Fund or reflect the beliefs or values of any particular investor. ESG standards differ by region and industry, and a company’s ESG practices or the Subadviser’s assessment of a company’s ESG practices may change over time. The Subadviser’s evaluation of a company also may be dependent on the availability of timely, complete and accurate ESG data reported by issuers and/or third party data providers. Different methodologies may be used by the various issuers and third party sources that provide ESG data, and such ESG data often lacks standardization, consistency and transparency.</div> <div style="margin-top:6pt;">Asset-Backed and Mortgage-Backed Securities Risk—investments in asset-backed and mortgage-backed securities involve risk of severe credit downgrades, loss due to prepayments that occur earlier or later than expected, illiquidity and default.</div> <div style="margin-top:6pt;">Changing Distribution Level Risk—the Fund will normally receive income which may include interest, dividends and/or capital gains, depending upon its investments. The distribution amount paid by the Fund will vary and generally depends on the amount of income the Fund earns (less expenses) on its portfolio holdings, and capital gains or losses it recognizes. A decline in the Fund’s income or net capital gains arising from its investments may reduce its distribution level.</div> <div style="margin-top:6pt;">Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars and exposure to non-U.S. currencies may subject the Fund to the risk that those currencies will decline in value relative to the U.S. dollar.</div> <div style="margin-top:6pt;">Emerging Markets Risk—investments in emerging markets are subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility. Such additional risks include the risk that markets in emerging market countries are typically less developed and less liquid than markets in developed countries and such markets are subjected to increased economic, political, or regulatory uncertainties.</div> <div style="margin-top:6pt;">Exchange-Traded Fund Risk—because ETFs incur their own costs, investing in them could result in a higher cost to the investor.</div> <div style="margin-top:6pt;">Extension Risk—during periods of rising interest rates, a debtor may pay back a bond or other fixed income security slower than expected or required, and the value of such security may fall.</div> <div style="line-height:10.6pt;text-align:left;">Foreign Investment Risk—investments in foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investments in U.S. issuers and may result in greater price volatility.</div> <div style="margin-top:6pt;">Inflation/Deflation Risk—inflation risk is the risk that the value of assets or income from investments will be worth less in the future. Inflation rates may change frequently and drastically as a result of various factors and the Fund’s investments may not keep pace with inflation, which may result in losses to Fund investors or adversely affect the real value of shareholders’ investments in the Fund. As inflation rates increase, fixed income securities markets may experience heightened levels of interest rate volatility and liquidity risk. Deflation risk is the risk that the prices throughout the economy decline over time – the opposite of inflation. Deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of the Fund’s portfolio.</div> <div style="margin-top:6pt;">Liquidity Risk—the Fund may not be able to dispose of particular investments, such as illiquid securities, readily at favorable times or prices or the Fund may have to sell them at a loss.</div> <div style="margin-top:6pt;">Management Risk—because the Fund is an actively managed investment portfolio, security selection or focus on securities in a particular style, market sector or group of companies may cause the Fund to incur losses or underperform relative to its benchmarks or other funds with a similar investment objective. There can be no guarantee that the Subadviser’s investment techniques and risk analysis will produce the desired result.</div> <div style="margin-top:6pt;">Municipal Market Risk—factors unique to the municipal bond market may negatively affect the value of municipal bonds. These factors include political or legislative changes, and uncertainties related to the tax status of the securities and the rights of investors in the securities. The Fund may invest in a group of municipal obligations that are related in such a way that an economic, business, or political development affecting one would also affect the others.</div> <div style="margin-top:6pt;">Prepayment Risk—a debtor may exercise its right to pay back a bond or other debt security earlier than expected or required during periods of decreasing interest rates.</div> <div style="margin-top:6pt;">Reinvestment Risk—the Fund may have difficulty reinvesting payments from debtors and may receive lower rates than from its original investments.</div> <div style="margin-top:6pt;">U.S. Government Securities Risk—obligations issued by some U.S. Government agencies, authorities, instrumentalities, or sponsored enterprises such as Government National Mortgage Association (“GNMA”) are backed by the full faith and credit of the U.S. Government, while obligations issued by others, such as Federal National Mortgage Association (“FNMA”), Federal Home Loan Mortgage Corporation (“FHLMC”), and Federal Home Loan Banks (“FHLBs”), are not backed by the full faith and credit of the U.S. Government and are backed solely by the entity’s own resources or by the ability of the entity to borrow from the U.S. Treasury. If one of these agencies defaults on a loan, there is no guarantee that the U.S. Government will provide financial support.</div> Performance <div style="line-height:10.6pt;margin-top:0.0pt;text-align:left;">The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund’s performance from year to year and by showing how the Fund’s performance compares to that of a broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. </div><div style="margin-top:6pt;">Effective February 27, 2017, outstanding Class S shares of the Fund (formerly Service Class shares, which were renamed Class S shares on October 1, 2016) were renamed Class N shares. Effective October 1, 2016, outstanding Institutional Class shares of the Fund were renamed Class I shares. </div><div style="margin-top:6pt;">As of March 19, 2021, GW&K was appointed as subadviser to the Fund and the Fund changed its name to “AMG GW&K ESG Bond Fund,” adopted its current investment strategies, including beginning to use ESG factor analysis as part of the Fund’s investment selection process, and began comparing its performance to the Bloomberg U.S. Aggregate Bond Index. The Fund’s performance information for periods prior to March 19, 2021 reflects the Fund’s investment strategy that was in effect at that time and would have been different had the Fund’s current investment strategy been in effect. </div><div style="margin-top:6pt;">To obtain updated performance information please visit wealth.amg.com or call 800.548.4539.</div> The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund’s performance from year to year and by showing how the Fund’s performance compares to that of a broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. wealth.amg.com 800.548.4539 Calendar Year Total Returns as of 12/31/25 (Class N) <div style="margin-top:9pt;">Best Quarter: 7.40% (4th Quarter 2023) Worst Quarter: -5.94% (2nd Quarter 2022)</div> Best Quarter: 0.0740 2023-12-31 Worst Quarter: -0.0594 2022-06-30 Average Annual Total Returns as of 12/31/25 0.0726 -0.0009 0.0273 0.0558 -0.0162 0.0116 0.0427 -0.0051 0.0156 0.0743 0.0011 0.0291 0.0730 -0.0036 0.0201 <div style="margin-top:6pt;">After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax </div><div style="line-height:10.6pt;text-align:left;">returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). After-tax returns are shown for Class N shares only, and after-tax returns for Class I shares will vary.</div> After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-taxreturns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). After-tax returns are shown for Class N shares only, and after-tax returns for Class I shares will vary. AMG Veritas Asia Pacific Fund Investment Objective <div style="line-height:10.6pt;margin-top:0.0pt;text-align:left;">AMG Veritas Asia Pacific Fund (the “Fund”) seeks to provide long-term capital appreciation.</div> Fees and Expenses of the Fund <div style="line-height:10.6pt;margin-top:0.0pt;text-align:left;">The table below describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</div> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0071 0.0071 0 0 0.0063 0.0039 0.0134 0.0110 -0.0017 -0.0017 0.0117 0.0093 Expense information has been restated to reflect current fees. May 1, 2027 Expense Example <div style="line-height:10.6pt;margin-top:-0.01pt;text-align:left;">This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund’s operating expenses remain the same. The first year of each amount shown in the Example </div><div style="line-height:10.6pt;text-align:left;">reflects the Fund’s contractual expense limitation through May 1, 2027. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:</div> 119 408 718 1598 95 333 590 1325 Portfolio Turnover <div style="line-height:10.6pt;margin-top:0.0pt;text-align:left;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 132% of the average value of its portfolio.</div> 1.32 Principal Investment Strategies <div style="line-height:10.6pt;margin-top:0.00pt;text-align:left;">The Fund principally invests in equity securities listed or traded on exchanges in the Asia Pacific region (excluding Japan). Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in securities of issuers located in the Asia Pacific region (excluding Japan). Under normal circumstances, the Fund considers equity securities to include common and preferred stocks, depositary receipts, and securities with equity characteristics, including, but not limited to, equity linked securities and participatory notes (P-Notes). The Fund considers an issuer to be located in the Asia Pacific region (excluding Japan) if the issuer has its registered office in the Asia Pacific region or has the predominant part of its commercial activity in the Asia Pacific region or, in the case of a holding company, it predominantly holds participations in companies with registered offices in the Asia Pacific region. </div><div style="margin-top:6pt;">The Fund intends to invest in focused equity positions, identified through the bottom-up, stock picking approach of Veritas Asset Management LLP, the subadviser to the Fund (“Veritas” or the “Subadviser”), with a macro overlay, an analysis of broader macroeconomic themes. The Subadviser’s macro analysis will focus on identifying long term themes and trends and then proceed to identifying companies within those identified themes and trends that it believes have sound business models, strong management and disciplined financial controls. The Fund seeks to focus on what it believes to be quality companies in sectors that the Subadviser believes show long term structural growth potential with emphasis on industry leaders or emerging leaders with durable competitiveness. The macro themes are identified via a combination of in-house and external research. Asian domestic demand is an example of a theme internal to the Subadviser. In part, the Fund uses this analysis to seek to identify opportunities to invest in companies in the Asia Pacific </div><div style="line-height:10.6pt;text-align:left;">region whose businesses are benefitting from rising consumer spending in the Asia Pacific region in consumer goods or services. </div><div style="margin-top:6pt;">The Fund intends to gain exposure to equities issued by companies located in the People’s Republic of China (“PRC”) through direct investments in equities listed on mainland China stock exchanges, such as the Shanghai and Shenzen stock exchanges, via Hong Kong through the market access program through which foreign investors can deal in select China A Shares (Stock Connect) or indirect exposure through P-Notes or similar equity linked securities. The Fund intends to gain exposure to equities issued by companies located in India through direct exposure or indirect exposure through P-Notes or similar equity linked securities. Equity linked securities are a type of derivative instrument that have a return component based on the performance of another security, and provide the Fund with an alternative to investing in the underlying security directly in situations where the Fund would have to register with a foreign exchange or foreign securities agency to be able to do so. P-Notes are a type of derivative instrument used by the Fund to access non-U.S. markets and to gain exposure to, primarily, equity securities of issuers listed on a non-U.S. exchange rather than purchasing securities directly. </div><div style="margin-top:6pt;">The Fund will generally invest in mid- to large-capitalization companies, although the Fund may also invest in small-capitalization companies. The Fund generally invests in companies with market capitalizations greater than $5 billion. The Fund currently expects to hold between 15 and 60 positions at any time. The Fund is non-diversified. </div><div style="margin-top:6pt;">The Fund may hold assets in cash and cash equivalents, and at times these holdings may be significant. The Fund’s cash level at any point typically relates to the Subadviser’s individual security selection process, and therefore may vary, depending on the Subadviser’s desired security weightings.</div> There is the risk that you may lose money on your investment. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. <div style="margin-top:6pt;">Market Risk—market prices of investments held by the Fund may fall rapidly or unpredictably due to a variety of factors, including economic or market conditions, or other factors including terrorism, war, natural disasters and the spread of infectious illness or other public health issues, including epidemics or pandemics, or in response to events that affect particular industries or companies. In addition, unexpected political, regulatory, trade and diplomatic events within the </div><div style="line-height:10.6pt;text-align:left;">United States and abroad may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.</div> <div style="margin-top:6pt;">Management Risk—because the Fund is an actively managed investment portfolio, security selection or focus on securities in a particular style, market sector or group of companies may cause the Fund to incur losses or underperform relative to its benchmarks or other funds with a similar investment objective. There can be no guarantee that the Subadviser’s investment techniques and risk analysis will produce the desired result.</div> <div style="margin-top:6pt;">Focused Investment Risk—to the extent the Fund invests a substantial portion of its assets in a relatively small number of securities or a particular market, industry, group of industries, country, region, group of countries, asset class or sector, it generally will be subject to greater risk than a fund that invests in a more diverse investment portfolio. In addition, the value of the Fund would be more susceptible to any single economic, market, political or regulatory occurrence affecting, for example, that particular market, industry, region or sector.</div> <div style="margin-top:6pt;">Foreign Investment Risk—investments in foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investments in U.S. issuers and may result in greater price volatility.</div> <div style="margin-top:6pt;">Geographic Focus Risk—to the extent the Fund focuses its investments in a particular country, group of countries or geographic region, the Fund is particularly susceptible to economic, political, regulatory or other events or conditions affecting such countries or region, and the Fund’s NAV may be more volatile than the NAV of a more geographically diversified fund and may result in losses. </div><div style="margin-top:6pt;">Greater China. The Fund is particularly susceptible to risks in the Greater China region, which consists of Hong Kong, The People’s Republic of China and Taiwan, among other countries. Economies in the Greater China region are dependent on the economies of other countries and can be significantly affected by currency fluctuations and increasing competition from other emerging economies in Asia with lower costs. Adverse events in any one country within the region may impact the other countries in the region or Asia as a whole. Markets in the Greater China region can experience significant volatility due to social, economic, regulatory and political uncertainties. Significant portions of the Chinese securities markets may become rapidly illiquid, as Chinese issuers have the ability to suspend the trading of their equity securities, and have shown a willingness to exercise that option in response to market volatility and other events. U.S. or foreign government sanctions or other investment restrictions or intervention could negatively affect the implementation of the Fund’s investment strategies, for example by precluding the Fund from making certain investments or causing the Fund to sell investments at disadvantageous times. China has yet to develop comprehensive securities, corporate, or commercial laws, its market is relatively new and less developed, and its economy may be adversely impacted by a slowdown in export growth. </div><div style="margin-top:6pt;">South Korea. Investments in South Korean issuers will subject the Fund to legal, regulatory, political, currency, security, and economic risks that are specific to South Korea. In addition, economic and political developments of South Korea’s neighbors, </div><div style="line-height:10.6pt;text-align:left;">including escalated tensions involving North Korea and any outbreak of hostilities involving North Korea, or the threat of an outbreak of such hostilities, may have a severe adverse effect on the South Korean economy. The South Korean economy is reliant on trading exports, and disruptions or decreases in trade activity could lead to declines in South Korea’s economic growth potential.</div> <div style="margin-top:6pt;">Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars and exposure to non-U.S. currencies may subject the Fund to the risk that those currencies will decline in value relative to the U.S. dollar.</div> <div style="margin-top:6pt;">Emerging Markets Risk—investments in emerging markets are subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility. Such additional risks include the risk that markets in emerging market countries are typically less developed and less liquid than markets in developed countries and such markets are subjected to increased economic, political, or regulatory uncertainties.</div> <div style="margin-top:6pt;">High Cash Balance Risk— when the Fund has a significant cash balance for a sustained period, the benefit to the Fund of any market upswing may likely be reduced, and the Fund’s performance may be adversely affected.</div> <div style="margin-top:6pt;">Large-Capitalization Stock Risk—the stocks of large-capitalization companies are generally more mature and may not be able to reach the same levels of growth as the stocks of small- or mid-capitalization companies.</div> <div style="margin-top:6pt;">Liquidity Risk—the Fund may not be able to dispose of particular investments, such as illiquid securities, readily at favorable times or prices or the Fund may have to sell them at a loss.</div> <div style="margin-top:6pt;">Non-Diversified Fund Risk—the Fund is non-diversified and therefore a greater percentage of holdings may be focused in a small number of issuers or a single issuer, which can place the Fund at greater risk. Notwithstanding the Fund’s status as a “non-diversified” investment company under the Investment Company Act of 1940 (the “1940 Act”), the Fund intends to qualify each year as a regulated investment company accorded favorable tax treatment under the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”), which imposes its own diversification requirements that are less restrictive than the requirements applicable to “diversified” investment companies under the 1940 Act. The Fund’s intention to qualify as a regulated investment company may limit its pursuit of its investment strategy and its investment strategy could limit its ability to so qualify.</div> <div style="margin-top:6pt;">Participatory Notes Risk—an investment in participatory notes is subject to market risk. The performance results of participatory notes may not exactly replicate the performance of the underlying securities. An investment in participatory notes is also subject to counterparty risk, relating to the non-U.S. bank or broker-dealer that issues the participatory notes, and may be subject to liquidity risk.</div> <div style="margin-top:6pt;">Political Risk—changes in the general political and social environment of a country can have substantial effects on the value of investments exposed to that country.</div> <div style="margin-top:6pt;">PRC Tax Risk—the application of the tax laws and regulations of the PRC to income, including capital gains, derived from certain investments of the Fund remains unclear, and may well </div><div style="line-height:10.6pt;text-align:left;">continue to evolve, possibly with retroactive effect. Any taxes imposed on the investments of the Fund pursuant to such laws and regulations will reduce the Fund’s overall returns.</div> <div style="margin-top:6pt;">Sector Risk—issuers and companies that are in similar industry sectors may be similarly affected by particular economic or market events; to the extent the Fund has substantial holdings within a particular sector, the risks associated with that sector increase. Stocks in the industrials and information technology sectors may comprise a significant portion of the Fund's portfolio. The industrials sector may be affected by general economic trends, including employment, economic growth and interest rates, changes in consumer confidence and spending, government regulation, commodity prices and competitive pressures. The information technology sector may be affected by technological obsolescence, short product cycles, falling prices and profits, competitive pressures and general market conditions.</div> <div style="margin-top:6pt;">Small- and Mid-Capitalization Stock Risk—the stocks of small- and mid-capitalization companies often have greater price volatility, lower trading volume, and less liquidity than the stocks of larger, more established companies.</div> <div style="margin-top:6pt;">Stock Connect Risk—trading in China A-Shares through Stock Connect is subject to sudden changes in quota limitations, application of trading suspensions, differences in trading days between the People's Republic of China and Stock Connect, operational risk, clearing and settlement risk and regulatory and taxation risk.</div> <div style="margin-top:6pt;">Value Stock Risk—value stocks may perform differently from the market as a whole and may be undervalued by the market for a long period of time.</div> <div style="margin-top:6pt;">Variable Interest Entity Risk—the Fund may gain investment exposure to certain Chinese companies through variable interest entity (“VIE”) structures. A VIE structure enables foreign investors, such as the Fund, to obtain investment exposure to a Chinese company in situations in which the Chinese government has limited or prohibited non-Chinese ownership of such company. A VIE does not have equity ownership in its corresponding China-based company but has claims to the China-based company’s profits and control of its assets through contractual arrangements. VIEs are a common industry practice and well known to officials and regulators in China; however, VIEs are not formally recognized under Chinese law. If the Chinese government takes action adversely affecting VIEs, the market value of the Fund’s associated portfolio holdings would likely suffer significant, detrimental, and possibly permanent consequences, which could result in substantial investment losses.</div> Performance <div style="line-height:10.6pt;margin-top:0.00pt;text-align:left;">The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund’s performance from year to year and by showing how the Fund’s performance compares to that of a broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. </div><div style="margin-top:6pt;">As of March 19, 2021, Veritas was appointed as subadviser to the Fund and the Fund changed its name to “AMG Veritas Asia Pacific Fund,” adopted its current investment strategies and began comparing its performance to the MSCI AC Asia Pacific </div><div style="line-height:10.6pt;text-align:left;">ex Japan Index. The Fund’s performance information for periods prior to March 19, 2021 reflects the Fund’s investment strategy that was in effect at that time and would have been different had the Fund’s current investment strategy been in effect. </div><div style="margin-top:6pt;">Effective February 27, 2017, outstanding Class S shares of the Fund (formerly Service Class shares, which were renamed Class S shares on October 1, 2016) were renamed Class N shares. Effective October 1, 2016, outstanding Institutional Class shares of the Fund were renamed Class I shares. </div><div style="margin-top:6pt;">To obtain updated performance information please visit wealth.amg.com or call 800.548.4539.</div> The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund’s performance from year to year and by showing how the Fund’s performance compares to that of a broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. wealth.amg.com 800.548.4539 Calendar Year Total Returns as of 12/31/25 (Class N) <div style="margin-top:9pt;">Best Quarter: 32.71% (2nd Quarter 2020) Worst Quarter: -23.48% (1st Quarter 2020)</div> Best Quarter: 0.3271 2020-06-30 Worst Quarter: -0.2348 2020-03-31 Average Annual Total Returns as of 12/31/25 0.4157 0.0145 0.0939 0.4160 -0.0097 0.0729 0.2472 0.0095 0.0740 0.4190 0.0170 0.0966 0.2956 0.0419 0.0847 <div style="margin-top:6pt;">After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). After-tax returns are shown for Class N shares only, and after-tax returns for Class I shares will vary.</div> After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). After-tax returns are shown for Class N shares only, and after-tax returns for Class I shares will vary. AMG Funds LLC (the “Investment Manager”) has contractually agreed, through at least May 1, 2027, to waive management fees and/or pay or reimburse the Fund’s expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest (including interest incurred in connection with bank and custody overdrafts and in connection with securities sold short), shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions and other transaction costs, dividends payable with respect to securities sold short, acquired fund fees and expenses, and extraordinary expenses) of the Fund to the annual rate of 0.43% of the Fund’s average daily net assets (this annual rate or such other annual rate that may be in effect from time to time, the “Expense Cap”), subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months after the date any amounts are paid, waived or reimbursed by the Investment Manager, the Investment Manager may recover such amounts from the Fund, provided that such repayment would not cause the Fund’s Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of the items noted in the parenthetical above) to exceed either (i) the Expense Cap in effect at the time such amounts were paid, waived or reimbursed, or (ii) the Expense Cap in effect at the time of such repayment by the Fund. The contractual expense limitation may only be terminated in the event the Investment Manager or a successor ceases to be the investment manager of the Fund or a successor fund, by mutual agreement between the Investment Manager and the AMG Funds III Board of Trustees or in the event of the Fund’s liquidation unless the Fund is reorganized or is a party to a merger in which the surviving entity is successor to the accounting and performance information of the Fund. Expense information has been restated to reflect current fees. AMG Funds LLC (the “Investment Manager”) has contractually agreed, through at least May 1, 2027, to waive management fees and/or pay or reimburse the Fund’s expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest (including interest incurred in connection with bank and custody overdrafts and in connection with securities sold short), shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions and other transaction costs, dividends payable with respect to securities sold short, acquired fund fees and expenses, and extraordinary expenses) of the Fund to the annual rate of 0.93% of the Fund’s average daily net assets (this annual rate or such other annual rate that may be in effect from time to time, the “Expense Cap”), subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months after the date any amounts are paid, waived or reimbursed by the Investment Manager, the Investment Manager may recover such amounts from the Fund, provided that such repayment would not cause the Fund’s Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of the items noted in the parenthetical above) to exceed either (i) the Expense Cap in effect at the time such amounts were paid, waived or reimbursed, or (ii) the Expense Cap in effect at the time of such repayment by the Fund. The contractual expense limitation may only be terminated in the event the Investment Manager or a successor ceases to be the investment manager of the Fund or a successor fund, by mutual agreement between the Investment Manager and the AMG Funds III Board of Trustees or in the event of the Fund’s liquidation unless the Fund is reorganized or is a party to a merger in which the surviving entity is successor to the accounting and performance information of the Fund.